title: Instantaneous drug delivery of magnetic/thermally sensitive nanospheres by a high-frequency magnetic field.
abstract: Novel dual-functional nanospheres composed of magnetic iron oxide nanoparticles embedded in a thermo-sensitive Pluronic F127 (F127) matrix were successfully synthesized by an in situ coprecipitation process. The nanospheres were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy. Experimental observations indicated that the F127 was subjected to a rapid structural change when the magnetic phase caused rapid heating after a short exposure to a high-frequency magnetic field. During the field duration, considerable volume shrinkage of the nanospheres (2.3-fold diameter reduction) was detected. This has been translated to an instantaneous release of a drug, Doxorubicin (DOX), when the DOX was encapsulated within the nanospheres. Such a rapidly responsive release of the DOX from the nanospheres was due to an intimate contact between the nanomagnet and F127, where an effective thermal and mechanical transfer between core and shell phases efficiently took place in the presence of the magnetic field.
authors.affiliation: Department of Materials Sciences and Engineering, National Chiao Tung University, Hsinchu, Taiwan, 300, Republic of China.
authors.forename: Ting-Yu
authors.initials: TY
authors.lastname: Liu
authors.forename: Shang-Hsiu
authors.initials: SH
authors.lastname: Hu
authors.forename: Kun-Ho
authors.initials: KH
authors.lastname: Liu
authors.forename: Ren-Shiuan
authors.initials: RS
authors.lastname: Shaiu
authors.forename: Dean-Mo
authors.initials: DM
authors.lastname: Liu
authors.forename: San-Yuan
authors.initials: SY
authors.lastname: Chen
mesh_terms: D004317:Doxorubicin / Q000737:chemistry*; D016503:Drug Delivery Systems; D004574:Electromagnetic Fields; D005290:Ferric Compounds / Q000737:chemistry; D008280:Magnetics; D054118:Nanospheres / Q000737:chemistry*; D010316:Particle Size; D020442:Poloxamer / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013499:Surface Properties; D013696:Temperature
chemical_list: D005290:Ferric Compounds; D020442:Poloxamer; C000499:ferric oxide; D004317:Doxorubicin